on a JDM engine whats a (OBD1) what does it do?

Answer 1

Most cars from 90-95 have a OBD1 system. 96 and up is OBD2 which is more advanced and a lot more of a pain to work with. With OBD1 you dont necessarily need a scan tool to read the codes. If your buying a jdm engine, you want to make sure that then engine is the same OBD as the car your putting it in. It is possible to convert back and forth and anyway really, its just easier if you get a engine that is the same OBD system. Most people run OBD1 because it is ALOT easier to tune and is less of a hassle. A good site to learn alot more about all of this is
www.pgmfi.org

Answer 2

OBD stands for On Board Diagnostics. The first generation is usually just referred to as OBD. OBD started in the late 80's/early 90's and there have been different generations. Different generations of OBD have different sensors and therefore the engines are often slightly different.

The seller is probably telling you this so that you can either match the engine to the car's computer (an OBD1 computer) or so that you'll know what other work you will need to do to swap the engine in (ie attaching new sensors and wiring them).

Answer 3

An OBD is an on board diagnostic feature which monitors the auto's computer and reads the computer chip when a problem of a mechanical nature is detected. An OBD reader is required if you wish to read or decipher the codes.